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        <td class="header">&nbsp;
            Definitions, Acronyms, Abbreviations
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<h3>Definition of Terms</h3>


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        <td>Product</td>


        <td>An object that contains remote sensing data for a&nbsp;scene on the earth. A product can contain meta-data,
            geo-coding
            information, tie-point grids and bands. All band raster datasets within
            a product have the same pixel resolution and share the same geo-coding.
        </td>

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        <td>Band</td>


        <td>A raster dataset of a product. The band's sample values are usually the
            measurements of a sensor.
        </td>

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        <td>Tie-point grid</td>


        <td>An auxiliary (geophysical) raster dataset of a product. Tie-point grids usually provide less sample values
            than a band. Missing values, with respect to the full pixel resolution of a product, are obtained by a
            linear interpolation. The tie-point grid data normally does&nbsp;not originate from the sensor which
            provided
            the product's measurement data.
        </td>

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        <td>Geo-Coding</td>


        <td>Provides the geodetic co-ordinates for a given pixel of a product.
            An image is geo-coded if it is somehow possible to find the geographical latitude and longitude values for
            any pixel.
            ENVISAT products store their geo-coding information in the tie-point grids
            named <code>latitude</code> and <code>longitude</code>. If a product has been map transformed,
            it is known to be geo-referenced and as such, tie-point information is no longer required.
        </td>

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        <td>Geo-Reference</td>


        <td>An image is geo-referenced if any point in the image can be found in a corresponding reference
            map by a linear transformation. Every pixel in the image has the same size if expressed in map units.
            Geo-referencing a
            geo-coded image includes image warping, applying a well known map projection and pixel re-sampling.
        </td>

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        <td>Map</td>


        <td>Graphic representation of the physical features (natural, artificial, or both) of a part or the whole of the
            Earth's surface, by means of signs and symbols or photographic imagery, at an established scale, on a
            specified
            projection, and with the means of orientation indicated.
        </td>

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        <td>Map Projection</td>


        <td>Orderly system of lines on a plane representing a corresponding system of
            imaginary lines on an adopted terrestrial or celestial datum surface. Also,
            the mathematical concept for such a system. For maps of the Earth, a projection
            consists of a graticule of lines representing parallels of latitude and
            meridians of longitude or a grid.
        </td>


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        <td>Graticule</td>


        <td>Network of parallels and meridians on a map or chart. A geographic graticule is a system of coordinates of
            latitude and longitude used to define the position of a point on the surface of the Earth with respect to
            the
            reference ellipsoid.
        </td>

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        <td>Grid</td>


        <td>In connection with maps: a network of uniformly spaced parallel lines intersecting at right angles.
            When superimposed on a map, it usually carries the name of the projection used for the map &#8211; that is,
            Lambert grid,
            transverse Mercator grid, universal transverse Mercator grid.
        </td>

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        <td>Pixel coordinates</td>


        <td>Pixel values always refer to the upper
            left corner of the pixel. Pixel co-ordinates are always zero based, the pixel at <code>X=0,Y=0</code> refers
            to the upper left
            pixel of an image and the upper left corner of that pixel.
        </td>

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        <td>Pixel value</td>


        <td>In general a composite of red, green and blue <i>sample values</i> resulting in a colour as part of an
            image.&nbsp;
        </td>

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        <td>Geodetic co-ordinates</td>


        <td>Geodetic co-ordinates are given as latitude and longitude values and always refer -
            if not otherwise stated - to the WGS-84 ellipsoid.
            The geodetic co-ordinates of a pixel, always refer to the upper left corner of the pixel.
        </td>

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<h3>Acronyms, Abbreviations</h3>


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    <td>AATSR</td>

    <td>Advanced Along Track Scanning Radiometer</td>

</tr>


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    <td>ADS</td>

    <td>Annotation Data Set in an ENVISAT data product</td>

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    <td>ASAR</td>

    <td>Advanced Synthetic Aperture Radar</td>

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    <td>BEAM</td>

    <td>Acronym for Basic ENVISAT Toolbox for (A)ATSR and MERIS</td>

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    <td>COTS</td>

    <td>Commercial Off-The-Shelf Software</td>

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    <td>ECSS</td>

    <td>European Co-operation for Space Standardisation (documents available at ESTEC at the
        Requirements and Standards Division)
    </td>

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    <td>EnviView</td>

    <td>Software developed at ESTEC to visualise and analyse the Envisat data. See User services
        section at <a href="https://earth.esa.int/eogateway/missions/envisat">https://earth.esa.int/eogateway/missions/envisat</a></td>
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    <td>EO</td>

    <td>Earth Observation</td>

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    <td>ESA</td>

    <td>European Space Agency (see <a href="http://www.esa.it/export/esaCP/index.html">http://www.esa.it/export/esaCP/index.html</a>)
    </td>

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    <td>ESRIN</td>

    <td>European Space Research Institute (see <a href="http://www.esa.it/export/esaCP/index.html">http://www.esa.it/export/esaCP/index.html</a>)
    </td>

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    <td>ESTEC</td>

    <td>European Space Research and Technology Centre (see
        <a href="http://www.esa.it/export/esaCP/index.html">http://www.esa.it/export/esaCP/index.html</a>)
    </td>

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    <td>ENVISAT</td>

    <td>ESA satellite (see <a href="https://earth.esa.int/eogateway/missions/envisat">https://earth.esa.int/eogateway/missions/envisat</a>)</td>
</tr>


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    <td>GADS</td>

    <td> Global Annotation Data Set in an ENVISAT data product</td>

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    <td>HDF</td>

    <td>Hierarchical Data Format (see <a href="https://www.hdfgroup.org/">https://www.hdfgroup.org/</a>)</td>
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    <td>HDF-EOS</td>

    <td>Extended HDF format (see <a href="http://ecsinfo.gsfc.nasa.gov/iteams/HDF-EOS/HDF-EOS.html">http://ecsinfo.gsfc.nasa.gov/iteams/HDF-EOS/HDF-EOS.html</a>)
    </td>


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    <td>MDS</td>

    <td>Measurement Data Set in an ENVISAT data product</td>

</tr>


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    <td>MERIS</td>

    <td>Medium Resolution Imaging Spectrometer Instrument (see <a
            href="https://earth.esa.int/eogateway/missions/envisat">https://earth.esa.int/eogateway/missions/envisat</a>)
    </td>

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    <td>MODIS</td>

    <td>Moderate Resolution Imaging Spectroradiometer (see <a href="http://modis.gsfc.nasa.gov/MODIS/">http://modis.gsfc.nasa.gov/MODIS/</a>)
    </td>


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    <td>MPH</td>

    <td>Main Product Header in an ENVISAT data product</td>

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    <td>NEST</td>
    <td>Next ESA SAR Toolbox</td>
</tr>
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    <td>OSSD</td>

    <td>Open Source Software Development</td>

</tr>


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    <td>SAR</td>

    <td>Synthetic Aperture Radar (<a href="http://earth.esa.int">http://earth.esa.int</a>)</td>

</tr>


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    <td>SPH</td>

    <td>Specific Product Header in an ENVISAT data product</td>

</tr>


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    <td>SW</td>

    <td>Software</td>

</tr>


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